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When to Plant Sunchoke in Atchison County, KS

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

Atchison County, Kansas is in USDA Zone 5b. The average last spring frost is April 17 and the first fall frost is October 21, giving you a growing season of approximately 187 days.

At an elevation of 678 feet, Atchison County receives approximately 25.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Sunchoke to ensure they mature before fall.

Atchison County, KS (Zone 5b) Moderate season
187 days
Last Spring Frost April 17
187 growing days
First Fall Frost October 21

Atchison County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (0 days to spare)
Transplant: Apr 26 🍅 Harvest: Aug 16 – Oct 11
Recommended (50%) ✓ Fits season (5 days to spare)
Transplant: May 1 🍅 Harvest: Aug 21 – Oct 16
Safe Start (90%) ✓ Fits season (9 days to spare)
Transplant: May 16 🍅 Harvest: Sep 5 – Oct 31

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,466 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Sunchoke needs ~1,690 GDD — county provides 2,431 GDD Excellent fit

Sunchoke Planting Timeline โ€” Atchison County, KS

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors May 1 May 1 โ€“ May 15
Harvest August 21 Aug 21 โ€“ Oct 16

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
July โ€”
August Harvest
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

110โ€“150 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 5b

Growing Season

187 days

Growing Tips for Atchison County

Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Sunchoke in Atchison County, KS?

Atchison County is in Zone 5b with an average last frost of April 17. Plan your Sunchoke planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Atchison County, KS?

Atchison County, Kansas is in USDA Hardiness Zone 5b. The average last spring frost is April 17 and first fall frost is October 21.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Atchison County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Atchison County, KS. Local conditions may vary. Last updated: April 2026.